LeetCode

LeetCode Algorithm

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#	Title	Solution	Difficulty
344	Reverse String	Objective-C、Swift	Easy
541	Reverse String II	Swift	Easy
345	Reverse Vowels of a String	Swift	Easy
258	Add Digits	Objective-C、Swift	Easy
389	Find the Difference	Objective-C、Swift	Easy
226	Invert Binary Tree	Objective-C、Swift	Easy
283	Move Zeroes	Objective-C、Swift	Easy
404	Sum of Left Leaves	Objective-C、Swift	Easy
409	Longest Palindrome	Objective-C、Swift	Easy
383	Ransom Note	Objective-C、Swift	Easy
237	Delete Node in a Linked List	Objective-C	Easy
349	Intersection of Two Arrays	Objective-C、Swift	Easy
100	Same Tree	Objective-C、Swift	Easy
171	Excel Sheet Column Number	Objective-C、Swift	Easy
242	Valid Anagram	Objective-C、Swift	Easy
169	Majority Element	Objective-C、Swift	Easy
387	First Unique Character in a String	Objective-C、Swift	Easy
217	Contains Duplicate	Objective-C、Swift	Easy
219	Contains Duplicate II	Swift	Easy
350	Intersection of Two Arrays II	Objective-C、Swift	Easy
13	Roman to Integer	Objective-C、Swift	Easy
412	Fizz Buzz	Objective-C、Swift	Easy
206	Reverse Linked List	Objective-C、Swift	Easy
415	Add Strings	Objective-C、Swift	Easy
405	Convert a Number to Hexadecimal	Objective-C、Swift	Easy
231	Power of Two	Objective-C、Swift	Easy
326	Power of Three	Objective-C、Swift	Easy
202	Happy Number	Objective-C、Swift	Easy
121	Best Time to Buy and Sell Stock	Objective-C、Swift	Easy
83	Remove Duplicates from Sorted List	Objective-C、Swift	Easy
70	Climbing Stairs	Objective-C、Swift	Easy
104	Maximum Depth of Binary Tree	Objective-C、Swift	Easy
461	Hamming Distance	Objective-C、Swift	Easy
476	Number Complement	Objective-C、Swift	Easy
496	Next Greater Element I	Objective-C、Swift	Easy
520	Detect Capital	Objective-C、Swift	Easy
371	Sum of Two Integers	Objective-C、Swift	Easy
657	Judge Route Circle	Swift	Easy
617	Merge Two Binary Trees	Swift	Easy
561	Array Partition I	Swift	Easy
500	Keyboard Row	Swift	Easy
557	Reverse Words in a String III	Swift	Easy
575	Distribute Candies	Swift	Easy
566	Reshape the Matrix	Swift	Easy
463	Island Perimeter	Swift	Easy
637	Average of Levels in Binary Tree	Swift	Easy
521	Longest Uncommon Subsequence I	Swift	Easy
485	Max Consecutive Ones	Swift	Easy
448	Find All Numbers Disappeared in an Array	Swift	Easy
653	Two Sum IV - Input is a BST	Swift	Easy
606	Construct String from Binary Tree	Swift	Easy
538	Convert BST to Greater Tree	Swift	Easy
492	Construct the Rectangle	Swift	Easy
598	Range Addition II	Swift	Easy
453	Minimum Moves to Equal Array Elements	Swift	Easy
530	Minimum Absolute Difference in BST	Swift	Easy
455	Assign Cookies	Swift	Easy
122	Best Time to Buy and Sell Stock II	Swift	Easy
167	Two Sum II - Input array is sorted	Swift	Easy
563	Binary Tree Tilt	Swift	Easy
599	Minimum Index Sum of Two Lists	Swift	Easy
661	Image Smoother	Swift	Easy
506	Relative Ranks	Swift	Easy
628	Maximum Product of Three Numbers	Swift	Easy
447	Number of Boomerangs	Swift	Easy
401	Binary Watch	Swift	Easy
504	Base 7	Swift	Easy
268	Missing Number	Swift	Easy
674	Longest Continuous Increasing Subsequence	Swift	Easy
543	Diameter of Binary Tree	Swift	Easy
551	Student Attendance Record I	Swift	Easy
671	Second Minimum Node In a Binary Tree	Swift	Easy
108	Convert Sorted Array to Binary Search Tree	Swift	Easy
594	Longest Harmonious Subsequence	Swift	Easy
572	Subtree of Another Tree	Swift	Easy
107	Binary Tree Level Order Traversal II	Swift	Easy
645	Set Mismatch	Swift	Easy
437	Path Sum III	Swift	Easy
53	Maximum Subarray	Swift	Easy
35	Search Insert Position	Swift	Easy
27	Remove Element	Swift	Easy
263	Ugly Number	Swift	Easy
21	Merge Two Sorted Lists	Swift	Easy
198	House Robber	Swift	Easy
257	Binary Tree Paths	Swift	Easy
1	Two Sum	Swift	Easy
118	Pascal's Triangle	Swift	Easy
119	Pascal's Triangle II	Swift	Easy
342	Power of Four	Swift	Easy
101	Symmetric Tree	Swift	Easy
367	Valid Perfect Square	Swift	Easy
66	Plus One	Swift	Easy
459	Repeated Substring Pattern	Swift	Easy
9	Palindrome Number	Swift	Easy
110	Balanced Binary Tree	Swift	Easy
26	Remove Duplicates from Sorted Array	Swift	Easy
643	Maximum Average Subarray I	Swift	Easy
441	Arranging Coins	Swift	Easy
501	Find Mode in Binary Search Tree	Swift	Easy
434	Number of Segments in a String	Swift	Easy
172	Factorial Trailing Zeroes	Swift	Easy
38	Count and Say	Swift	Easy
112	Path Sum	Swift	Easy
507	Perfect Number	Swift	Easy
205	Isomorphic Strings	Swift	Easy
438	Find All Anagrams in a String	Swift	Easy
20	Vaild Parentheses	Swift	Easy
290	Word Pattern	Swift	Easy
720	Longest Word in Dictionary	Swift	Easy
724	Find Pivot Index	Swift	Easy
680	Valid Palindrome II	Swift	Easy
58	Length of Last Word	Swift	Easy
88	Merge Sorted Array	Swift	Easy
203	Remove Linked List Elements	Swift	Easy
633	Sum of Square Numbers	Swift	Easy
686	Repeated String Match	Swift	Easy
111	Minimum Depth of Binary Tree	Swift	Easy
234	Palindrome Linked List	Swift	Easy
687	Longest Univalue Path	Swift	Easy
7	Reverse Integer	Swift	Easy
14	Longest Common Prefix	Swift	Easy
414	Third Maximum Number	Swift	Easy
605	Can Place Flowers	Swift	Easy
400	Nth Digit	Swift	Easy
443	String Compression	Swift	Easy
475	Heaters	Swift	Easy
69	Sqrt(x)	Swift	Easy
204	Count Primes	Swift	Easy
28	Implement strStr()	Swift	Easy
168	Excel Sheet Column Title	Swift	Easy
581	Shortest Unsorted Continuous Subarray	Swift	Easy
125	Valid Palindrome	Swift	Easy
788	Rotated Digits	Swift	Easy
189	Rotate Array	Swift	Easy
665	Non-decreasing Array	Swift	Easy
669	Trim a Binary Search Tree	Swift	Easy
532	K-diff Pairs in an Array	Swift	Easy
693	Binary Number with Alternating Bits	Swift	Easy
695	Max Area of Island	Swift	Easy
696	Count Binary Substrings	Swift	Easy
697	Degree of an Array	Swift	Easy
717	1-bit and 2-bit Characters	Swift	Easy
733	Flood Fill	Swift	Easy
748	Largest Number At Least Twice of Others	Swift	Easy
682	Baseball Game	Swift	Easy
479	Largest Palindrome Product	Swift	Easy
744	Find Smallest Letter Greater Than Target	Swift	Easy
747	Min Cost Climbing Stairs	Swift	Easy
760	Find Anagram Mappings	Swift	Easy
762	Prime Number of Set Bits in Binary Representation	Swift	Easy
482	License Key Formatting	Swift	Easy
771	Jewels and Stones	Swift	Easy
766	Toeplitz Matrix	Swift	Easy
442	Find All Duplicates in an Array	Swift	Medium
540	Single Element in a Sorted Array	Swift	Medium
654	Maximum Binary Tree	Swift	Medium
515	Find Largest Value in Each Tree Row	Swift	Medium
260	Single Number III	Swift	Medium
513	Find Bottom Left Tree Value	Swift	Medium
728	Self Dividing Numbers	Swift	Medium
537	Complex Number Multiplication	Swift	Medium
406	Queue Reconstruction by Height	Swift	Medium
419	Battleships in a Board	Swift	Medium
647	Palindromic Substrings	Swift	Medium
553	Optimal Division	Swift	Medium
413	Arithmetic Slices	Swift	Medium
739	Daily Temperatures	Swift	Medium
508	Most Frequent Subtree Sum	Swift	Medium
462	Minimum Moves to Equal Array Elements II	Swift	Medium
667	Beautiful Arrangement II	Swift	Medium
495	Teemo Attacking	Swift	Medium
451	Sort Characters By Frequency	Swift	Medium
655	Print Binary Tree	Swift	Medium
238	Product of Array Except Self	Swift	Medium
712	Minimum ASCII Delete Sum for Two Strings	Swift	Medium
725	Split Linked List in Parts	Swift	Medium
565	Array Nesting	Swift	Medium
347	Top K Frequent Elements	Swift	Medium
672	Bulb Switcher II	Swift	Medium
94	Binary Tree Inorder Traversal	Swift	Medium
477	Total Hamming Distance	Swift	Medium
503	Next Greater Element II	Swift	Medium
646	Maximum Length of Pair Chain	Swift	Medium
526	Beautiful Arrangement	Swift	Medium
454	4Sum II	Swift	Medium
421	Maximum XOR of Two Numbers in an Array	Swift	Medium
648	Replace Words	Swift	Medium
22	Generate Parentheses	Swift	Medium
39	Combination Sum	Swift	Medium
216	Combination Sum III	Swift	Medium
623	Add One Row to Tree	Swift	Medium
343	Integer Break	Swift	Medium
144	Binary Tree Preorder Traversal	Swift	Medium
498	Diagonal Traverse	Swift	Medium
2	Add Two Numbers	Swift	Medium
445	Add Two Numbers II	Swift	Medium
592	Fraction Addition and Subtraction	Swift	Medium
539	Minimum Time Difference	Swift	Medium
12	Integer to Roman	Swift	Medium
241	Different Ways to Add Parentheses	Swift	Medium
378	Kth Smallest Element in a Sorted Matrix	Swift	Medium
318	Maximum Product of Word Lengths	Swift	Medium
230	Kth Smallest Element in a BST	Swift	Medium
650	2 Keys Keyboard	Swift	Medium
392	Is Subsequence	Swift	Medium
423	Reconstruct Original Digits from English	Swift	Medium
583	Delete Operation for Two Strings	Swift	Medium
337	House Robber III	Swift	Medium
287	Find the Duplicate Number	Swift	Medium
78	Subsets	Swift	Medium
740	Delete and Earn	Swift	Medium
791	Custom Sort String	Swift	Medium
547	Friend Circles	Swift	Medium
763	Partition Labels	Swift	Medium
494	Target Sum	Swift	Medium
524	Longest Word in Dictionary through Deleting	Swift	Medium
46	Permutations	Swift	Medium
229	Majority Element II	Swift	Medium
319	Bulb Switcher	Swift	Medium
424	Longest Repeating Character Replacement	Swift	Medium
377	Combination Sum IV	Swift	Medium
137	Single Number II	Swift	Medium
516	Longest Palindromic Subsequence	Swift	Medium
89	Gray Code	Swift	Medium
328	Odd Even Linked List	Swift	Medium
102	Binary Tree Level Order Traversal	Swift	Medium
394	Decode String	Swift	Medium
48	Rotate Image	Swift	Medium
199	Binary Tree Right Side View	Swift	Medium
390	Elimination Game	Swift	Medium
636	Exclusive Time of Functions	Swift	Medium
684	Redundant Connection	Swift	Medium
96	Unique Binary Search Trees	Swift	Medium
62	Unique Paths	Swift	Medium
807	Max Increase to Keep City Skyline	Swift	Medium
309	Best Time to Buy and Sell Stock with Cooldown	Swift	Medium
692	Top K Frequent Words	Swift	Medium
525	Contiguous Array	Swift	Medium
77	Combinations	Swift	Medium
435	Non-overlapping Intervals	Swift	Medium
59	Spiral Matrix II	Swift	Medium
64	Minimum Path Sum	Swift	Medium
153	Find Minimum in Rotated Sorted Array	Swift	Medium
738	Monotone Increasing Digits	Swift	Medium
3	Longest Substring Without Repeating Characters	Swift	Medium
5	Longest Palindromic Substring	Swift	Medium
6	ZigZag Conversion	Swift	Medium
535	Encode and Decode TinyURL	Objective-C	Medium